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The cross-sections show that the ground elevation for the <br />majority of the stations has increased es much as four <br />inches. This is because subsidence above panel two is <br />causing a cantilever effect that is forcing the surrounding <br />ground to push up. <br />The cross-sections also show as much as one foot of surface <br />settlement in areas not predicted to subside. This is ex- <br />pected since the monuments in these areas are located on re- <br />claimed spoil from strip mining. Surface settlement is <br />shown in the cross-sections as areas where the change in <br />ground elevation is uniform to a side of a subsidence <br />basin. <br />The end points for the angle of draw were determined incor- <br />porating the definition for surface settlement written <br />above. The definition was adequate for determining end <br />points on sides of the subsidence basin in rows S and NPR, <br />but not in row H. The end point on the dowodip side of the <br />gob in row H could not be determined since its in an area <br />where the affects of the cantilever action and surface set- <br />tlement have not reached equilibrium. However, an angle of <br />drew for the downdip aide of row H will be determined when <br />row H has been undermined by the second longwall panel. <br />The angle of draw and end points locations are '.has follows: <br /> END ANGLE OF <br />ROW POINT DRAW COINMBNT <br />H BETWEEN -6.4 DECREES UPDIP SIDS OF GOB <br /> R-19 AND H-20 <br />S 5-11 17.2 DEGREES DOWNDIP SIDE OF GOB <br />S S-22 8.9 DEGREES UPDIP S:[DE OF GOB <br />NPR P-3 14.2 DEGREES BBHIND GOB <br />The angle of draw and the maximum subsidence shown above <br />are all within the predicted ranges submitted i.n Empires' <br />permit. The permit predicted the maximum subsidence to be <br />8-feet and the maximum angle of draw to be 20 degrees. <br />The monitoring points will be surveyed again in September <br />and December of 1986. Results from these surveys will be <br />submitted in the next semi-annual report. <br />